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131.
132.
Effect of normobaric hypoxia on the testis in a murine model   总被引:1,自引:0,他引:1  
High‐altitude hypoxia generates spermiogram impairment due to germinal epithelium, Leydig cells, sperm and seminal plasma alterations, but precise mechanisms involved are unknown. The objective of this work was to analyse the effect of normobaric hypoxia on the morphology of testicular interstitium and some associated molecular and hormonal factors. Twenty‐four mice were exposed to normobaric hypoxia (8.1% inspired oxygen fraction) during 20 days. The effects on body weight, testicular weight, vascularisation, testosterone, HIF1‐α and VEGF were analysed at different periods of exposure and compared to controls. Hypoxic mice had lower body weight than mice kept in normoxia. Testicular weight raised significantly the 1st day, but remained normal during the rest of experiment. Number of blood vessels per field and mean diameter of vessels were higher in hypoxic mice. Plasmatic and testicular testosterone raised during first 24 h of hypoxia, but decreased on the 5th day. Vascular/interstitial ratio (proportion of interstice occupied by blood vessels) duplicated at the end of the experiment. Most substantial early effects of hypoxia were testicular oedema, increase in number and diameter of blood vessels and elevation of plasmatic and testicular testosterone. Normobaric hypoxia generates similar effects to those induced by hypobaric hypoxia.  相似文献   
133.
PURPOSE: To compare the refractive results of laser epithelial keratomileusis (LASEK) and laser in situ keratomileusis (LASIK) for the correction of low myopia. METHODS: A prospective, interventional, non-randomized, observer-masked study was performed of patients with myopia of < or = -2.50 diopters (D) (cylinder < or = 1.50 D) who had undergone either LASEK or LASIK. Refractive analysis was performed by a masked observer preoperatively and 1 day, 1 week, and 1 and 3 months postoperatively. RESULTS: Seventy-nine eyes that fulfilled the inclusion criteria in each group were included in the study. No statistically significant differences were noted in age, gender, or preoperative refractive error between groups. Postoperative uncorrected visual acuity (UCVA) was significantly lower in LASEK eyes 1 and 7 days postoperatively (P = .0001). At 1 and 3 months postoperatively, no significant differences were noted between the groups in UCVA (P = .07), but best spectacle-corrected visual acuity 3 months postoperatively was significantly better in LASEK eyes (P = .01). The refractive error was similar in both groups (P = .3). CONCLUSIONS: Visual improvement after LASEK for low myopia is significantly slower than after LASIK. Visual outcomes at 3 months postoperatively were similar with both techniques for the correction of low myopia.  相似文献   
134.
Neonatal lupus erythematosus (NLE) is an infrequent disease in newborns caused by the transplacental passage of maternal Anti-Ro/SSA, Anti-La/SSB and/or Anti-U1 RNP antibodies. The most common manifestations are cutaneous and cardiac. We carried out a retrospective study of cases of NLE diagnosed in the last 10 years at the Hospital Universitario Insular in Gran Canaria. Complete data was obtained for 4 patients. Three cases had circulating Anti-Ro antibodies in the mother and in the newborns, while in the fourth case they were Anti-RNP. Two mothers were diagnosed with systemic lupus, one with mixed connective tissue disease and the other with leucocytoclastic vasculitis. The skin lesions consisted of urticaria-like and desquamative lesions. One patient presented with ulceration. The histological study of the urticaria-like lesions showed a non-specific perivascular infiltrate; the desquamative lesions were consistent with subacute lupus erythematosus.  相似文献   
135.
BACKGROUND: Herpes simplex virus type 2 (HSV-2) is among the most prevalent sexually transmitted diseases worldwide. In Mexico there is a lack of population-based HSV-2 surveys. GOALS: To determine population-based HSV-2 seroprevalence and risk factors among women in Mexico City. STUDY DESIGN: A random sample of 730 women was identified among the residents of Mexico City. Women ages 25 to 85 years were selected from 3,694 households. Western blot serology testing was conducted on serum samples to determine HSV-2 type-specific serostatus. A structured questionnaire was administered, and multivariate analyses were performed to identify risk factors for HSV-2 seropositivity, which were stratified into two age categories: younger than 50 years of age and 50 years of age or older. RESULTS: The HSV-2 seroprevalence among female participants was 29.8%, with a significant trend of increasing HSV-2 prevalence for each higher level of age (P < 0.001). Female participants had a median age of 46 years and were predominantly monogamous (82.6%). The overall population-based seroprevalence estimated in Mexico City among women was 35.8%. The independent risk factors for HSV-2 seropositivity included a history of two or more sexual partners (odds ratio [OR], 2.2; 95% CI, 1.4-3.4), two or more sexual partners before first pregnancy (OR, 2.3; 95% CI, 1.4-3.7), cohabitation with partner (OR, 2.5; 95% CI, 1.3-4.7), and current vaginal douching (OR, 1.7; 95% CI, 1.2-2.6). CONCLUSIONS: Population-based HSV-2 seroprevalence is endemically high among middle-age women in Mexico City, and clearly is correlated with higher-risk sexual behavior. This elevated HSV-2 seroprevalence may reflect unrecognized HSV-2 transmission throughout life.  相似文献   
136.
We report on the case of a patient with myelodysplastic syndrome (MDS) who presented with leukaemia cutis preceding development of acute myeloid leukaemia. Leukaemic infiltration of the skin should be considered an early manifestation of leukaemic transformation and an indicator of poor prognosis in MDS.  相似文献   
137.
Petiveria alliacea is a plant traditionally known for its anti-inflammatory and anti-tumor activities; however, the molecular and cellular mechanisms of its immunomodulatory properties are still unknown. Dendritic cells (DC) promote adaptive immune response by activating T lymphocytes, inducing an effector response or tolerance depending on the DC differentiation level. Herein, we evaluated the immunomodulatory activity of aqueous and organic plant fractions from P. alliacea using human monocyte-derived dendritic cells. The phenotype, cytokine secretion and gene expression were estimated after treatment with the plant fractions. We found that P. alliacea aqueous fraction induced morphological changes and co-stimulatory expression of CD86, indicating partial DC maturation. In addition, pro-inflammatory cytokines such as IL-1β, IL-6, IL-8, IL-10, IL-12p70, and TNF-α were secreted. The fraction also increased NF-κB gene expression while down-regulating TGFβ gene expression. These results suggest that the aqueous fraction can induce partial DC activation, a situation that can be relevant in tolerance induction. It is important to state that the organic fraction by itself does not show any immunomodulatory activity. This study provides evidence for possible immunomodulatory activity of P. alliacea extracts which has been used in traditional medicine in Colombia.  相似文献   
138.
We present a case-control study that evaluated the association of Chlamydia-negative, Ureaplasma-negative nongonococcal urethritis with oral and/or anal sex. The study population was composed of 120 patients diagnosed as having nongonococcal urethritis in the Diagnostic Center for sexually transmitted diseases (STD) of the Medical School of Seville. Cases were 56 men suffering from nonogonococcal urethritis from whom neither Chlamydia trachomatis nor Ureaplasma urealyticum was isolated; the remaining 64 males with cultures positive for these agents were considered as controls. Insertive genital-oral intercourse significantly increased the risk of Chlamydia-negative, Ureaplasma-negative nongonococcal urethritis (odds ratio, 11.400; 95% confidence interval, 2.357-75.057). This association was still very strong (odds ratio, 8.882) after adjustment for homosexuality. Insertive anal intercourse appears not to increase the risk of Chlamydia-negative, Ureaplasma-negative nongonococcal urethritis. We conclude that insertive oral sex can be an important risk factor in the development of nongonnococcal urethritis in which the microbial agent is still unknown.  相似文献   
139.
Grupo de Estudio de la Sobrevida en la Insuficiencia Cardiaca en Argentina (GESICA) studied whether a standardized protocol for the initiation and titration of the β-blocker carvedilol in a multicenter, open-label program would optimize β-blocker use in heart failure (HF) patients. The program included: (1) the carvedilol initiation and titration period, and (2) long-term follow-up at 6 and 12 months. Of 1299 patients in the registry, 504 were excluded due to current therapy; of the remaining 795 eligible patients, 293 were excluded due to contraindications. Of the included patients with follow-up data (n = 316), 93.3% tolerated carvedilol initiation and 47.7% of the patients reached the target dose of 50 mg/day for a mean dose of 39 mg/day. Rates were comparable in the elderly (n = 83), of which 53% achieved a target dose for a mean dose of 43.08 mg/day. This protocol improved therapy rates and achieved target doses quickly (average of 4 visits). Concomitant medications did not have to be adjusted and there were low withdrawal rates (10%) and hospital admissions (7.2%) for HF. Patients were able to maintain carvedilol therapy at 6 and 12 months. These results indicate that a standardized titration protocol, as used in GESICA, for the initiation and titration of β-blockers is well tolerated and may improve β-blocker use in carefully selected heart failure patients.The study authors are members of the GESICA Steering Committee and Subcommittees  相似文献   
140.
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